I installed moodle 1.0.8 and would like to share the following experiences:
1. If you have an existing 1.0.7 installation, don't use the "mdl_" prefix in config.php. This creates an additional set of tables with the mdl_ extension and the system ignores your old tables, which emans all your settings are lost.
If that happens, drop all tables and reimport your old tables (you did back them up, didn't you?) and redo the admin thingy.
2. Martin - 1.0.8 is still not talking to the PostNuke member database. You did a wonderful job of hacking my 1.0.7 system, but the changes are not in 1.0.8